There's a famous German product line called Klasse. They have a product specifically for the interior previously known as VLRP (vinyl, leather, rubber,plastic) now called Klasse Cleaner Protectant. I would also give this a shot, another German product, called 1Z Leather while your in there cleaning stuff. It leaves the seats looking new, amazing how many layers of dyes from your jeans, pollution, etc. get stuck on a roadster interior.
KLASSE VINYL, LEATHER, RUBBER & PLASTIC-CLEANER/PROTECTANT
1Z Einszett Leather Care